/*
 * 微信公众号 H5 - 微信 JS-SDK
 * 签名接口 /wechat-share 需要 Bearer token，须在登录成功后调用
 */
import { ROOTPATH, WECHAT_APPID } from '@/common/config.js'

const DEFAULT_JS_API = [
	'getLocation',
	'openLocation',
	'updateAppMessageShareData',
	'updateTimelineShareData'
]

const SIGNATURE_APIS = [
	'/api/mobile/user/wechat-share',
	'/api/mobile/user/wechat-login-url'
]

let wxInstance = null
let wxInitPromise = null

export function isWechatBrowser() {
	return typeof navigator !== 'undefined' && /MicroMessenger/i.test(navigator.userAgent)
}

export function getStoredToken() {
	const walksz_lifeData = uni.getStorageSync('walksz_lifeData') || {}
	return walksz_lifeData.vuex_token || ''
}

export function resetWxJssdk() {
	wxInitPromise = null
}

/**
 * 参与签名的页面 URL（须与后端 wechat-share 入参 url 完全一致）
 * 后端常按 https://域名/h5walksz/ 带尾斜杠签名
 */
export function getSignPageUrl() {
	let url = window.location.href.split('#')[0]
	if (url.endsWith('/h5walksz')) {
		url += '/'
	}
	return url
}

function buildJsApiList(serverList) {
	const required = [
		'getLocation',
		'openLocation',
		'updateAppMessageShareData',
		'updateTimelineShareData',
		'onMenuShareTimeline',
		'onMenuShareAppMessage'
	]
	const merged = [...(Array.isArray(serverList) ? serverList : []), ...required]
	return Array.from(new Set(merged))
}

/**
 * 解析 wechat-share 返回（根级含 appId/nonceStr/timestamp/signature/jsApiList）
 */
export function normalizeSignaturePayload(body) {
	if (!body) return null
	let payload = body
	if (typeof payload === 'string') {
		try {
			payload = JSON.parse(payload)
		} catch (e) {
			return null
		}
	}
	if (payload.data && payload.data.signature) {
		payload = payload.data
	}
	if (!payload.signature) return null
	const timestamp = payload.timestamp || payload.timeStamp
	const nonceStr = payload.nonceStr || payload.noncestr
	if (!timestamp && timestamp !== 0) return null
	if (!nonceStr) return null
	return {
		signature: payload.signature,
		timestamp: String(timestamp),
		nonceStr,
		appId: payload.appId || payload.appid || WECHAT_APPID,
		jsApiList: buildJsApiList(payload.jsApiList),
		signUrl: payload.url || ''
	}
}

function getAuthHeader() {
	const token = getStoredToken()
	return token ? { Authorization: `Bearer ${token}` } : {}
}

function parseWxSignatureResponse(res) {
	if (!res || res.statusCode !== 200) return null
	let body = res.data
	if (!body) return null
	if (body.errcode !== undefined && body.errcode !== 0) {
		console.warn('微信签名接口返回错误:', body.errcode, body.errmsg || body.message)
		return null
	}
	return normalizeSignaturePayload(body)
}

const loadWxSDK = () => {
	return new Promise((resolve, reject) => {
		if (typeof window === 'undefined') {
			reject(new Error('非浏览器环境'))
			return
		}
		if (window.wx) {
			wxInstance = window.wx
			resolve(wxInstance)
			return
		}
		const script = document.createElement('script')
		script.src = 'https://res.wx.qq.com/open/js/jweixin-1.6.0.js'
		script.onload = () => {
			wxInstance = window.wx
			resolve(wxInstance)
		}
		script.onerror = () => reject(new Error('加载微信 JS-SDK 失败'))
		document.head.appendChild(script)
	})
}

function requestWxSignature(apiPath) {
	const token = getStoredToken()
	if (!token) {
		return Promise.reject(new Error('未登录，无法获取微信签名'))
	}
	return new Promise((resolve, reject) => {
		const pageUrl = getSignPageUrl()
		uni.request({
			url: `${ROOTPATH}${apiPath}`,
			method: 'GET',
			header: getAuthHeader(),
			data: {
				url: pageUrl,
				activity_tag: 'walksz',
				activity_list_id: 13
			},
			success: (res) => {
				const parsed = parseWxSignatureResponse(res)
				if (parsed) {
					resolve(parsed)
				} else {
					reject(new Error(`签名数据无效: ${apiPath}`))
				}
			},
			fail: (err) => reject(err)
		})
	})
}

const getWxSignature = async () => {
	let lastErr = null
	for (let i = 0; i < SIGNATURE_APIS.length; i++) {
		try {
			return await requestWxSignature(SIGNATURE_APIS[i])
		} catch (e) {
			lastErr = e
			console.warn('尝试签名接口失败:', SIGNATURE_APIS[i], e.message || e)
		}
	}
	throw lastErr || new Error('获取微信签名失败')
}

function setupShare(wx, shareConfig = {}) {
	const link = shareConfig.link || window.location.href.split('#')[0]
	const imgUrl = shareConfig.imgUrl || `${window.location.origin}/h5walksz/static/share.jpg`
	wx.updateAppMessageShareData({
		title: shareConfig.title || '打卡苏州市党史教育基地',
		desc: shareConfig.desc || '打卡苏州市党史教育基地',
		link,
		imgUrl
	})
	wx.updateTimelineShareData({
		title: shareConfig.title || '打卡苏州市党史教育基地',
		link,
		imgUrl
	})
}

/**
 * 使用已拿到的签名数据配置 JSSDK（推荐：通过 $u.api.share 获取签名）
 */
export function configWechatJssdk(signatureData, options = {}) {
	const parsed = normalizeSignaturePayload(signatureData)
	if (!parsed) {
		return Promise.reject(new Error('微信签名数据格式不正确'))
	}
	if (wxInitPromise) return wxInitPromise

	const pageUrl = getSignPageUrl()
	if (parsed.signUrl && parsed.signUrl !== pageUrl) {
		console.warn('微信签名 URL 与当前页不一致，可能导致 config 失败', {
			signUrl: parsed.signUrl,
			pageUrl
		})
	}

	wxInitPromise = loadWxSDK()
		.then(() => {
			return new Promise((resolve, reject) => {
				wxInstance.config({
					debug: false,
					appId: parsed.appId || WECHAT_APPID,
					timestamp: parsed.timestamp,
					nonceStr: parsed.nonceStr,
					signature: parsed.signature,
					jsApiList: options.jsApiList || parsed.jsApiList || DEFAULT_JS_API
				})
				wxInstance.ready(() => {
					if (options.setupShare !== false) {
						setupShare(wxInstance, options.shareConfig)
					}
					if (typeof options.onReady === 'function') {
						options.onReady(wxInstance)
					}
					resolve(wxInstance)
				})
				wxInstance.error((res) => {
					wxInitPromise = null
					console.error('wx.config 失败:', res)
					reject(res)
				})
			})
		})
		.catch((err) => {
			wxInitPromise = null
			throw err
		})

	return wxInitPromise
}

export function ensureWechatJssdk(options = {}) {
	if (!isWechatBrowser()) {
		return Promise.reject(new Error('非微信内置浏览器'))
	}
	if (!getStoredToken()) {
		return Promise.reject(new Error('请先登录后再使用微信地图能力'))
	}
	if (wxInitPromise) return wxInitPromise
	return getWxSignature().then((data) => configWechatJssdk(data, options))
}

export function getWechatLocation() {
	return ensureWechatJssdk({ setupShare: false }).then((wx) => {
		return new Promise((resolve, reject) => {
			wx.getLocation({
				type: 'gcj02',
				success: (res) => {
					resolve({
						longitude: res.longitude,
						latitude: res.latitude
					})
				},
				cancel: () => reject(new Error('用户取消定位')),
				fail: (err) => reject(err)
			})
		})
	})
}

export function openWechatLocation(lat, lng, name, address = '') {
	return ensureWechatJssdk({ setupShare: false }).then((wx) => {
		return new Promise((resolve, reject) => {
			wx.openLocation({
				latitude: parseFloat(lat),
				longitude: parseFloat(lng),
				name: name || '目的地',
				address: address || '',
				scale: 16,
				success: resolve,
				fail: reject
			})
		})
	})
}

const initWxSDK = (shareConfig = {}) => {
	return ensureWechatJssdk({ shareConfig, setupShare: true })
}

export {
	loadWxSDK,
	getWxSignature,
	initWxSDK
}